• 대한전기학회논문지
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• 제34권9호
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• pp.368-375
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• 1985

This paper describes the OPTIMAL PWM strategy to reduce harmonic losses for a variaboe-speed drive of an induction motor. This OPTIMAL theory is the strategy which can reduce motor losses by defining harmonic losses as a performance index and achieving it's minimization. This PWM strategy is compared with the conventional NATURAL PWM technique by a numerical method, and verified the validity of numerical method by a result of implementing in a practical 1 Hp-3 Phase induction motor drive system. Also, we could achieve a maximum efficiency to drive an induction motor by selecting appropriately one alternative between OPTIMAL and NATURAL PWM techniques, and employing it in a full driving range.

• Smart Structures and Systems
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• 제1권2호
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• pp.121-140
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• 2005

This paper presents a systematic investigation of the effect of sensor location on the data quality and subsequently, on the effectiveness of machine health monitoring. Based on an analysis of the signal propagation process from the defect location to the sensor, numerical simulations using finite element modeling were conducted on a bearing test bed to determine the signal strength at several representative sensor locations. The results showed that placing sensors closely to the machine component being monitored is critical to achieving high signal-to-noise ratio, thus improving the data quality. Using millimeter-sized piezoceramic plates, the obtained results were evaluated experimentally. A comparison with a set of commercial vibration sensors verified the developed structural dynamics-based sensor placement strategy. It further demonstrated that the proposed shock wave-based sensing technique provided an effective alternative to vibration measurement, while requiring less space for sensor installation.

• 경영과학
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• 제28권1호
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• pp.159-167
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• 2011

The theory of random utility maximization (RUM) defines the probability of an alternative being chosen as the probability of its utility being perceived as higher than those of all the other competing alternatives in the choice set (Marschak 1960). According to this theory, consumers perceive the utility of an alternative not as a constant but as a probability distribution. Over the last two decades, there have been an increasing number of studies on the effect of utility variance on choice probability. The common result of the previous studies is that as the utility variance increases, the effect of the mean value of the utility (the deterministic component of the utility) on choice probability is reduced. This study provides a theoretical investigation on the effect of utility variance on choice probability without any assumptions on the specific forms of probability distributions. This study suggests that without assumptions of the probability distribution functions, firms cannot apply the marketing strategy of maximizing choice probability (or market share), but can only adopt the strategy of maximizing the minimum or maximum value of the expected choice probability. This study applies the Chebyshef inequality and shows how the changes in utility variances affect the maximum of minimum of choice probabilities and provides managerial implications.

• 통상정보연구
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• 제14권2호
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• pp.81-119
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• 2012

본 연구에서는 유통경로 상의 지배구조 유형이 기업성과에 미치는 영향에 대해 실증적으로 검증해 보았다. 수출유통의 성과를 극대화 하기위한 일반적 전략대안은 수직적 통합에 의한 성과관리이다. 그러나 수출유통에 있어서 소유구조에 의한 수직적 통합은 용이하지 않은 경우가 대부분이다. 본 연구의 결과, 소유구조 이외에도 다양한 관계전략으로 유통성과 관리가 가능하다는 것을 알 수 있었다. 본 연구의 전략적 시사점으로, 수출유통경로결정에 있어서, 소유구조이외에도 거래관계구조 상의 정보교류, 협력관계, 신뢰관계 확립 등을 통하여 유통경로의 수직적 통합과 같은 수준의 성과를 이루어 낼 수 있다는 것을 제시할 수 있다.

• 동아시아경상학회지
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• 제8권4호
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• pp.29-43
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• 2020

Purpose - Although it has been 10 years since the university technology holding company was launched, it is currently facing operational limitations. The purpose of this study is to study the growth strategy of university technology holding companies by investigating the status and problems of university technology holding companies. Research design, data, and methodology - In this study, the status of university technology holding companies was analyzed based on the survey data issued by the University Technology Holding Companies Association. Due to the lack of research on university technology holding companies, policy alternatives were suggested by examining problems based on literature research. Result - In this study, an alternative to strengthening the competitiveness of technology holding companies and supporting policies was suggested. As a result of the research, it was discovered as a policy alternative to enhance the independence of technology-owned subsidiaries, develop outstanding talents, and expand the marketing of support programs to create results based on technology holding companies. Conclusion - In previous studies, alternatives to technology commercialization policies have been suggested, but studies on the role and status of detailed technology holding companies are insufficient, and the operation system of technology holding companies and discovery of future growth models are insufficient compared to overseas cases. Therefore, in this study, various policy innovation measures are presented as examples.

• Animal Bioscience
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• 제35권8호
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• pp.1109-1120
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• 2022

Antibiotics used to be supplemented to animal feeds as growth promoter and as an effective strategy to reduce the burden of pathogenic bacteria present in the gastro-intestinal tract. However, in-feed antibiotics also kill bacteria that may be beneficial to the animal. Secondly, unrestricted use of antibiotics enhanced the antibiotic resistance in pathogenic bacteria. To overcome above problems, scientists are taking a great deal of measures to develop alternatives of antibiotics. There is convincing evidence that probiotics could replace in-feed antibiotics in poultry production. Because they have beneficial effects on growth performance, meat quality, bone health and eggshell quality in poultry. Better immune responses, healthier intestinal microflora and morphology which help the birds to resist against disease attack were also identified with the supplementation of probiotics. Probiotics establish cross-feeding between different bacterial strains of gut ecosystem and reduce the blood cholesterol level via bile salt hydrolase activity. The action mode of probiotics was also updated according to recently published literatures, i.e antimicrobial substances generation or toxin reduction. This comprehensive review of probiotics is aimed to highlight the beneficial effects of probiotics as a potential alternative strategy to replace the antibiotics in poultry.

• Journal of Information Technology Applications and Management
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• 제18권4호
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• pp.81-93
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• 2011

By using GOSST theory, this paper models SSCFLP taking FLP, capacity of the facilities, single source capacitated limitation level and service enhancement issues into consideration. GOSST theory is strongly suggested as the solution procedure for these issues. We have used clustering of Center of Gravity method using the case study of the company S and then, took a heuristic GOSST measure in the alternative selection process. As a result, the research finds an alternative solution that both meets the satisfactory level of service and achieves consistent distribution capacity. When using this modeling, especially, to select the location of the logistics distribution center, the efficiency of current facilities is maximized while offering the minimum geometric distance for the alternative. Also, we can expect that the illustrated model and alternative solution can be applied to architecture of distribution system, to selection of telecommunication system locations for wireless network and to relocation of related facilities due to their sensitivities to location and weight.

• 한국주거학회논문집
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• 제22권6호
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• pp.1-10
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• 2011

In relation to the environmental analysis system of social marketing, this study has analyzed the responses made by the future users of the integrated apartments for the elderly that are currently under development as an alternative for the housing of the aging society. By studying the comprehensive social benefits, individual benefits and the implied factors for conceptual and behavioral changes in terms of the integrated apartments for the elderly, some important study results were obtained for the practical application of the new alternative. The major points are as follows: Firstly, from social aspect, the respondents wanted to know in detail about the integrated apartments for the elderly, the new alternative was evaluated to be helpful in elderly life, and it was expected to be effective for supporting the elderly people from psychological aspect. Secondly, from supply aspect, it was revealed that an alternative for the integrated apartment for the elderly is required to be developed in details reflecting the diverse needs of the elderly people and to be developed with differentiating strategy, but its applicability may confront some difficulties. Thirdly, from private aspect, the respondents showed they would feel economic burden if an integrated apartment for the elderly is introduced actually.

• Asian Journal of Atmospheric Environment
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• 제8권1호
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• pp.59-68
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• 2014

The Fukushima nuclear accident in 2011 had an extensive impact on the national electricity plans. This paper outlines alternative electricity scenarios that meet the goals of nuclear phase-out and greenhouse gas (GHG) emission reduction. This paper also analyzes the results of each scenario in respect to the electricity mix, GHG emissions, costs and employment effects. The Long-range Energy Alternatives Planning system (LEAP) model was used to simulate the annual electricity demand and supply system from 2011 to 2030. The reference year was 2009. Scenarios are reference (where existing plans are continued), A1, A2, B1, B2, and C2 (where the levels of demand management and nuclear phase-out are different). The share of renewable energy in the electricity mix in 2030 for each scenario will be increased from about 1% in 2009 to 8% in the reference scenario and from 11% to 31% in five alternative scenarios. Total cumulative cost increases up to 14% more than the reference scenario by replacing nuclear power plants with renewable energy in alternative scenarios could be affordable. Deploying enough renewable energy to meet such targets requires a roadmap for electricity price realization, expansion of research, development and deployment for renewable energy technologies, establishment of an organization dedicated to renewable energy, and ambitious targets for renewable energy.

• 한국경제지리학회지
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• 제13권3호
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• pp.498-513
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• 2010

이 논문은 최근 대안적인 지역개발의 방식으로 각광받고 있는 장소마케팅 전략을 비판적으로 분석하는 것을 목적으로 한다. 특히, 장소마케팅 개념이 인간주의 지리학자들에 의해 제시된 본질주의적 장소개념에 바탕을 두고 있어, 장소간 경쟁을 심화시키고, 장소를 폐쇄적이고 배타적인 영역으로 만드는 장소의 영역화를 결과할 가능성이 큼을 주장한다. 이를 위해 장소마케팅이 바탕을 두고 있는 본질주의 장소개념을 비판적으로 검토하고, 장소는 복잡한 권력관계 속에서 사회, 정치, 문화적 과정에 의해 구성된다는 최근의 대안적 논의를 소개할 것이다. 그리고, 영역이 만들어지는 사회-정치적 과정을 소개하면서, 영역이 장소의 특수한 한 형태임을 강조하고, 이를 바탕으로 장소마케팅이 장소를 영역화하는 전략임을 논증할 것이다.